The present invention relates to a fishing reel having a spool rotational-speed control means for controlling the rotational speed of a spool when the spool is freely rotated. More particularly, the present invention relates to a fishing reel having a spool rotational-speed control means which uses magnetic force to control the rotational speed when the spool is freely rotated.
When casting is performed with a fishing reel, the spool is brought to a free rotation permitted state. When the casting operation has been performed and thus the tackle has been thrown in a required direction, a fishing line is, together with the tackle, drawn from the spool at high speed immediately after casting has been performed. Therefore, also the spool is rotated at high speed. As the tackle is moved away from the spool, influences of resistance of air, wind and the like exerted on the tackle and the fishing line cause the flying speeds of the tackle and the fishing line adjacent to the tackle to be lowered as compared with the circumferential speed of the spool (that is, the flying speed of the fishing line immediately after it has been cast from the spool). When the tackle has reached the water surface, the tension of the fishing line, which is generated by dint of the kinetic energy of the tackle, is canceled. As a result, a great looseness, which is so-called "backlash", takes place between the tackle and the fishing reel. The backlash of the fishing line causes the fishing line to get entangled and the same to be caught by a fishing line, a fishing rod or another substance. What is worse, the tackle cannot move as required.
Hitherto, the backlash which takes place in the casting operation has been prevented by bringing the finger in contact with the spool to generate frictional braking force so that excessive rotations of the spool by dint of the inertia of the spool are prevented. However, adjustment of the frictional braking force with the finger for the purpose of preventing the backlash while elongating the distance of casting of the tackle is a difficult skill permitted for only an experienced person in casting.
Therefore, a spool rotational-speed control means which permits a person which is not skilled in casting to appropriately control the rotational speed of the spool when the spool is freely rotated has been researched and developed in recent years. The spool rotational-speed control means is classified into two major types. One of the two types of the spool rotational-speed control means has been disclosed in, for example, Japanese Utility-Model Laid-Open No. 3-79665. The foregoing spool rotational-speed control means has a structure that centrifugal force is used to cause frictional force to act on the spool which is being rotated freely. Another type of the spool rotational-speed control means has been disclosed in Japanese Utility-Model Publication No. 6-8695, Japanese Utility-Model Publication No. 6-16511 and Japanese Utility-Model Publication No. 63-34528. The foregoing spool rotational-speed control means have an arrangement that magnetic force is caused to act on the spool which is rotated freely.
The spool rotational-speed control means having a structure as disclosed in Japanese Utility-Model Laid-Open No. 3-79665 and arranged to use the centrifugal force to cause frictional force to act on the spool comprises a radial-directional movable member which is able to move in the radial direction of the spool shaft and which is disposed at an end of the spool shaft. The body of the reel has a truncated cone recess covering an end of the spool shaft. The radial-directional movable member at the end of the spool shaft is moved to the outside of the spool shaft in the radial direction of the same by dint of centrifugal force generated in the radial-directional movable member. Thus, the radial-directional movable member slides on the inner surface of the recess of the truncated cone recess of the body of the reel so that frictional force is generated which controls the rotational speed of the spool.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 6-8695 and using magnetic force has a structure that the spool is provided with a cylindrical projection made of a conductive material, the cylindrical projection projecting over an end surface of the spool concentrically with the spool. The body of the reel has double annular members disposed concentrically so that the cylindrical projection of the spool is received by the portion between the annular members. A plurality of magnets are, at the same intervals, disposed in the circumferential direction of each of the double annular members of the body of the reel. When the cylindrical projection made of the conductive material is, together with the spool, rotated relatively to each of the magnets at a position between the double annular members of the body of the reel, an eddy current is generated. As a result, electromagnetic force is generated which brakes the rotation of the spool together with the cylindrical projection made of the conductive material. The outer annular member of the double annular members of the body of the reel is movable relatively to the inner annular member in the circumferential direction in a predetermined range. The outer annular member can be moved in the circumferential direction in the predetermined range by using an adjustment button provided for the body of the reel. Thus, the positions of the plural magnets of the outer annular member with respect to the plural magnets of the inner annular member can be shifted in the circumferential direction in the predetermined range. As a result, the magnitude of the magnetic forces acting between the plural magnets of the inner annular member and the plural magnets of the outer annular member can be changed. Thus, the rotation of the cylindrical projection made of the conductive material together with the spool with respect to each magnet of the double annular members changes the level of the generated eddy current. Therefore, the magnitude of the electromagnetic force for braking the rotation of the spool together with the cylindrical projection made of the conductive material is changed so that the rotational speed of the spool is controlled.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 6-16511 and using magnetic force has a structure that the spool is made of a conductive material. Moreover, a magnet is provided for the body of the reel at a position corresponding to an end surface of the spool. The foregoing magnet is movable in a predetermined range in a direction along the center line of rotation of the spool by operating an adjustment button provided for the body of the reel. Thus, the distance to an end surface of the spool can be changed within a predetermined range. As a result, the magnitude of the magnetic force of the magnet which acts on the end surface of the spool can be changed. Moreover, the rotation of the spool with respect to the magnet of the body of the reel changes the level of the generated eddy current. Therefore, the magnitude of the electromagnetic force for braking the rotation of the spool can be changed so that the rotational speed of the spool is controlled.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 63-34525 and using magnetic force has a structure that the spool is provided with a cylindrical projection made of a conductive material, the cylindrical projection projecting over an end surface of the spool concentrically with the spool. The body of the reel has double annular members disposed concentrically so that the cylindrical projection of the spool is received by the portion between the annular members. A plurality of I- magnets are, at the same intervals, disposed in the circumferential direction of each of the double annular members of the body of the reel. When the cylindrical projection made of the conductive material is, together with the spool, rotated relatively to each of the magnet at a position between the double annular members of the body of the reel, an eddy current is generated. As a result, electromagnetic force is generated which brakes the rotation of the spool together with the cylindrical projection made of the conductive material. The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 63-34528 is provided with an adjustment button provided for the body of the reel. The adjustment button is operated so that a magnetic-force insulating member disposed between the outer annular member of the body of the reel and the cylindrical projection of the spool is concentrically projected and retracted in a direction along the center line of the rotation of the spool in a predetermined range. When the magnetic-force insulating member is projected or retracted between the outer annular member of the body of the reel and the cylindrical projection of the spool by operating the adjustment button, the magnitude of the magnetic force which acts on a portion between the plural magnets of the inner annular member and the plural magnets of the outer annular member is changed. Thus, the cylindrical projection made of the conductive material is, together with the spool, rotated with respect to each of the magnets of the double annular members so that the level of the eddy current which is generated is changed. As a result, the magnitude of the electromagnetic force for braking the rotation of the spool together with the cylindrical projection made of the conductive material can be changed. As a result, the rotational speed of the spool can be controlled.
A spool rotational-speed control means using both of the frictional force which is generated by dint of centrifugal force and magnetic force has been disclosed in Japanese Utility-Model Publication No. 62-35329.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 62-35329 comprises a radial-directional movable member which is able to move in the radial direction of the spool shaft and which is disposed at an end of the spool shaft. The body of the reel has a cylindrical recess covering an end of the spool shaft. The radial-directional movable member at the end of the spool shaft is moved to the outside of the spool shaft in the radial direction of the same by dint of centrifugal force generated in the radial-directional movable member. Thus, the radial-directional movable member slides on the inner surface of the recess of the cylindrical recess of the body of the reel so that frictional force is generated which controls the rotational speed of the spool.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 62-35329 is further provided with a cylindrical projection made of a conductive material, the cylindrical projection projecting over an end surface of the spool concentrically with the spool. The body of the reel has double annular members disposed concentrically so that the cylindrical projection of the spool is received by the portion between the annular members. A plurality of magnets are, at the same intervals, disposed in the circumferential direction of each of the double annular members of the body of the reel. When the cylindrical projection made of the conductive material is, together with the spool, rotated relatively to each of the magnet at a position between the double annular members of the body of the reel, an eddy current is generated. As a result, electromagnetic force is generated which brakes the rotation of the spool together with the cylindrical projection made of the conductive material. The outer annular member of the double annular members of the body of the reel is movable relatively to the inner annular member in the circumferential direction in a predetermined range. The outer annular member can be moved in the circumferential direction in the predetermined range by using an adjustment button provided for the body of the reel. Thus, the positions of the plural magnets of the outer annular member with respect to the plural magnets of the inner annular member can be shifted in the circumferential direction in the predetermined range. As a result, the magnitude of the magnetic forces acting between the plural magnets of the inner annular member and the plural magnets of the outer annular member can be changed. Thus, the rotation of the cylindrical projection made of the conductive material together with the spool with respect to each magnet of the double annular members changes the level of the generated eddy current. Therefore, the magnitude of the electromagnetic force for braking the rotation of the spool together with the cylindrical projection made of the conductive material is changed so that the rotational speed of the spool is controlled.
A spool rotational-speed control means using frictional force which is generated by centrifugal force in two steps has been disclosed in Japanese Patent Laid-Open No. 5-68455.
The spool rotational-speed control means disclosed in Japanese Patent Laid-Open No. 5-68455 has a first radial-directional movable member which is capable of moving in the radial direction of the spool shaft, the first radial-directional movable member being disposed at an end of the spool shaft. The body of the reel is provided with rotative cylindrical member for covering an end of the spool shaft concentrically with the spool shaft. Also the outer surface Leo of the cylindrical member is provided with a second radial-directional movable member which is capable of moving in the radial direction of the cylindrical member. The body of the reel has a circular recess for covering the outer surface of the cylindrical member concentrically with the cylindrical member.
The first radial-directional movable member at the end of the spool shaft is moved to the outside of the spool shaft in the radial direction of the spool shaft by relatively small centrifugal force which is generated in the first radial-directional movable member at relatively low rotational speed of the spool. Thus, the first radial-directional movable member slides on the inner surface of the rotative cylindrical member of the body of the reel so that the relatively low rotational speed of the spool is controlled. When the rotational speed of the spool has been raised to relatively high speed, the frictional force which is generated between the first radial-directional movable member and the inner surface of the cylindrical member is enlarged. As a result, also the cylindrical member starts rotating together with the spool. Thus, a second radial-directional movable member of the cylindrical member is moved to the outside of the spool shaft in the radial direction of the spool shaft by dint of relatively large centrifugal force which is generated in the second radial-directional movable member at relatively high rotational speed of the spool. Thus, the second radial-directional movable member slides in the circular recess of the body of the reel to generate frictional force. Thus, the relatively high rotational speed of the spool can be controlled.
The spool rotational-speed control means disclosed in the Japanese Utility-Model Laid-Open No. 3-79665 uses centrifugal force frictional force generated by dint of centrifugal force. If the state of the frictional surface between the radial-directional movable member at the end of the spool shaft and the inner surface of the truncated cone recess is changed because of adhesion of water or dust or because of abrasion, the frictional braking force which is generated by the spool rotational-speed control means is changed at a predetermined rotational speed of the spool. Therefore, the above-mentioned spool rotational-speed control means has a problem in that the frictional braking force cannot be stabilized. Another problem arises in that excessive noise is generated because the frictional force is used.
Two cases are considered, one of which is realized when the centrifugal force acting on the radial-directional movable member at the end of the spool shaft, that is, the rotational speed of the spool is higher than a predetermined speed and the radial-directional movable member slides on the inner surface of the truncated cone recess under relatively strong pressure. Another case is realized when the centrifugal force acting on the radial-directional movable member at the end of the spool shaft, that is, the rotational speed of the spool is lower than a predetermined speed and the radial-directional movable member slides on the inner surface of the truncated cone recess under relatively low pressure. The frictional braking force which is generated by the radial-directional movable member at the end of the spool shaft and which acts on the inner surface of the truncated cone recess of the body of the reel is changed two-dimensionally with respect to the rotational speed of the spool (the frictional force which is generated by dint of centrifugal force is in proportion to the square of the rotational speed of the spool). Therefore, the frictional braking force of the spool rotational-speed control means acting on the spool is rapidly changed. Therefore, when the rotational speed of the spool has been lowered in the final step of the casting operation, the amount of reduction in the rotational speed of the spool is reduced rapidly as compared with the amount of reduction in the flying speed of the tackle or that of the moving speed. As a result, the backlash of the fishing line can easily take place. Hitherto, the generation of the backlash phenomenon in the final step of the casting operation has been prevented by a so-called "thumbing operation" which is performed in such a manner that the surface of the fishing line wound around the spool is pressed by the finger of the hand of a fisher man who is holding the fishing rod to delicately control the rotational speed of the spool. However, an appropriate thumbing skill can be acquired only from experience.
If the rotational speed of the spool has been raised to a level higher than a predetermined speed after the casting operation has been performed, the spool rotational-speed control means using the frictional force generated by the centrifugal force encounters rapid enlargement of the frictional braking force. Thus, the rotational speed of the spool is rapidly lowered and the flying speed of the tackle is lowered rapidly. That is, the distance for which the tackle can be cast is shortened.
That is, the spool rotational-speed control means using the frictional force generated by the centrifugal force encounters the fact that the distance to be cast is shortened. Thus, the backlash phenomenon cannot perfectly be prevented in spite of superiority to a structure having no spool rotational-speed control means.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 6-8695, Japanese Utility-Model Publication No. 6-16511 and Japanese Utility-Model Publication No. 63-34528 and using magnetic force has the structure that the braking force is generated in substantially proportion to the rotational speed of the spool. Therefore, the spool rotational-speed control means of the foregoing is free from considerable change in the braking force generated in accordance with predetermined rotational speed of the spool and experienced with the spool rotational-speed control means using the frictional force generated by the centrifugal force. Therefore, generation of the backlash phenomenon in the casting operation can reliably be prevented. Therefore, even a beginner is able to easily perform the casting operation.
Since braking force corresponding to the rotational speed of the spool is always generated during the rotations of the spool, the distance for which the tackle can be cast cannot be elongated as required for a person who plays fishing in a final step of the casting operation. Moreover, even if casting for a short distance (so-called "short casting") is performed, the spool cannot freely be rotated and thus the rotational speed of the spool is too low for a person which plays fishing to cast the tackle to a required position.
The spool rotational-speed control means disclosed in Japanese Utility-Model Publication No. 62-35329 and using both of frictional force and magnetic force which are generated by dint of centrifugal force encounters a fact that the braking force generated by the magnetic force mainly acts on the spool in a range in which the rotational speed of the spool is relatively low. If the rotational speed of the spool is raised to relatively high speed, also braking force generated by the frictional force generated by the centrifugal force acts on the spool in addition to the braking force generated by the magnetic force. Thus, the problem experienced with the spool rotational-speed control means arranged to use magnetic force to use only the frictional force generated by the centrifugal force in that backlash takes place in a range in which the rotational speed of the spool is relatively low can be prevented. However, the problems experienced with the spool rotational-speed control means using only the frictional force generated by the centrifugal force in that noise is generated and the rotational speed of the spool is considerably changed at a predetermined number of revolutions of the spool occurring because of the change in the frictional braking force cannot completely be solved. Since the braking force generated by the magnetic force and/or the frictional force generated by the magnetic force and the centrifugal force acts on the overall rotational speed range for the spool, there arises a problem in that the distance for the tackle to be flown is shortened as compared with the spool rotational-speed control means using the magnetic force and the spool rotational-speed control means using frictional force generated by the centrifugal force.
The spool rotational-speed control means disclosed in Japanese Patent Laid-Open No. 5-68455 and arranged to use frictional force in two steps cannot solve the problem in that noise is generated and the rotational speed of the spool is changed at a predetermined number of revolutions of the spool because of the change in the frictional braking force. Moreover, a complicated structure is required in which a plurality of braking units are joined so as to sequentially be operated. Therefore, the overall size of the fishing reel having the spool rotational-speed control means of the foregoing type is enlarged excessively and the manufacturing cost cannot be reduced.